/*
The four adjacent digits in the 1000-digit number that have the greatest product are 9 × 9 × 8 × 9 = 5832.

73167176531330624919225119674426574742355349194934
96983520312774506326239578318016984801869478851843
85861560789112949495459501737958331952853208805511
12540698747158523863050715693290963295227443043557
66896648950445244523161731856403098711121722383113
62229893423380308135336276614282806444486645238749
30358907296290491560440772390713810515859307960866
70172427121883998797908792274921901699720888093776
65727333001053367881220235421809751254540594752243
52584907711670556013604839586446706324415722155397
53697817977846174064955149290862569321978468622482
83972241375657056057490261407972968652414535100474
82166370484403199890008895243450658541227588666881
16427171479924442928230863465674813919123162824586
17866458359124566529476545682848912883142607690042
24219022671055626321111109370544217506941658960408
07198403850962455444362981230987879927244284909188
84580156166097919133875499200524063689912560717606
05886116467109405077541002256983155200055935729725
71636269561882670428252483600823257530420752963450
Find the thirteen adjacent digits in the 1000-digit number that have the greatest product. What is the value of this product?

Anser:23514624000
Time:27.308µs
*/
package main

import (
	"fmt"
	"strings"
	"time"
)

func main() {
	tstart := time.Now()

	str := []string{
		"73167176531330624919225119674426574742355349194934",
		"96983520312774506326239578318016984801869478851843",
		"85861560789112949495459501737958331952853208805511",
		"12540698747158523863050715693290963295227443043557",
		"66896648950445244523161731856403098711121722383113",
		"62229893423380308135336276614282806444486645238749",
		"30358907296290491560440772390713810515859307960866",
		"70172427121883998797908792274921901699720888093776",
		"65727333001053367881220235421809751254540594752243",
		"52584907711670556013604839586446706324415722155397",
		"53697817977846174064955149290862569321978468622482",
		"83972241375657056057490261407972968652414535100474",
		"82166370484403199890008895243450658541227588666881",
		"16427171479924442928230863465674813919123162824586",
		"17866458359124566529476545682848912883142607690042",
		"24219022671055626321111109370544217506941658960408",
		"07198403850962455444362981230987879927244284909188",
		"84580156166097919133875499200524063689912560717606",
		"05886116467109405077541002256983155200055935729725",
		"71636269561882670428252483600823257530420752963450",
	}
	max := 0
	s := strings.Join(str, "")
	for i, count := 0, len(s); i+12 < count; i++ {
		tmp := 1
		for j := i; j < i+13; j++ {
			tmp *= int(s[j]) - 48
		}
		if max < tmp {
			max = tmp
		}
	}
	fmt.Println(max)
	tend := time.Now()
	fmt.Println(tend.Sub(tstart))
}
